Clearly, the Earth has limited resources and capacity is not clear that technological progress will yield more rapidly than the Malthusian logic. Stephen Hawking gave this newspaper a simple, clear and frightening phrase: "The survival of the human race depends on its ability to find new homes elsewhere in the universe, as the risk of a disaster destroys the Earth is growing" . It is evident that the planet has a limited capacity of resources (food, energy) and it is not clear that technological progress will yield more rapidly than the Malthusian logic. Economist Kenneth Boulding coined the term "Spaceship Earth" to explain the restricted nature of the enclosure in which the species lives . It is simple because it exposes both the problem and the solution-the universe is an endless source of energy, metals and minerals, as you know astrophysicists and science fiction fans; and it is terrifying because it places the planet before the vertigo of a distant destination, but final.
In Interstellar, and ninguneada last film by Christopher Nolan, he appeared this summary from the poster idea "Humanity was born on Earth, but is not destined to die in it." The message, similar to Hawking, was tacking plausible: the world population languishes in a slow extinction, smothered by giant dust storms and malignant degradation of agricultural production. The solution is to migrate to other similar and distant planets. The ideology of the film, however, is cornered and dangerous. By declaring that the essence of human nature is conquering and expansive, Interstellar release the man, for the sake of biological imperative, their responsibility to the planet and draw a predator future inhabit a planet until exhaustion exploit and occupy the next.
A group of physicists, astrophysicists and writers speculated, since the mid-sixties, with the idea of the universe as a space that can be colonized and exploited. Carl Sagan, Fred Hoyle, Freeman Dyson and Arthur C. Clarke applied his fertile imagination ( The Sentinel, matrix 2001, A Space Odyssey, was born one of those brainstorming) to design an interplanetary economy in which it is possible to generate atmosphere Mars to make it habitable, engineering terraform planets and planetoids using or exploiting the resources of the solar system. The technology will make us the space merchants.
Hawking today, as before Sagan or Clarke, columbran a very distant future, but for them ineluctable and ruthless. However, short-term exploitation of the immediate space is unattainable for the global economy. No exact calculations, but a profitable flow of space travel requires higher world GDP increases by at least 20% to the current; convert the flow in economic exchange would require an accumulation of capital well above the 20% added. The Wars will be a conflict of converting land on Mars, metals seekers against agricultural colonies on Io or solar panels against Mercury gas extraction; ie accumulation of capital and profitability. We do not know anything else.